MLB.com's Carrie Muskat has been covering Major League Baseball since 1981 and is the author of "Banks to Sandberg to Grace: Five Decades of Love and Frustration with the Cubs." You can follow her on Twitter @CarrieMuskat. Here, she blogs about the Cubs.

8/4 Silva still being tested

Carlos Silva was able to play catch Wednesday but is still undergoing tests to determine what caused the abnormal heart rate that forced him out of his last start.

Silva was pulled Sunday after facing four batters in Colorado, spent the night at a Denver hospital, and flew back to Chicago Monday. He was being examined by cardiologist Mark Upton.

Silva was placed on the disabled list Monday to give him time to get treatmeent. But during his throw session Wednesday, he showed he hasn’t lost his stuff.

“He throws a pretty good sinker,” said Carlos Zambrano, who played catch with Silva under the watchful eye of athletic trainer Mark O’Neal. “I thought I had a good sinker but I think he’s close or similar to my sinker.”

Meta

The following are trademarks or service marks of Major League Baseball entities and may be used only with permission of Major League Baseball Properties, Inc. or the relevant Major League Baseball entity: Major League, Major League Baseball, MLB, the silhouetted batter logo, World Series, National League, American League, Division Series, League Championship Series, All-Star Game, and the names, nicknames, logos, uniform designs, color combinations, and slogans designating the Major League Baseball clubs and entities, and their respective mascots, events and exhibitions.